Bubble tray for gas washing apparatus

ABSTRACT

A bubble tray for gas washing apparatus adapted to carry a blanket of wash liquid and having rows of holes through which the gases pass into the liquid. A curved deflector plate forming a circular channel is disposed over each row of holes with a longitudinal opening registering with the holes to receive the rising gases. The gases enter the channel tangentially through a constricted passage to cause the liquid to rotate therein and to deposit the entrained particles centrifugally onto the circular walls of the plate.

United States Patent [1 1 Dunn Apr. 30, 1974 BUBBLE TRAY FOR GAS WASHING2,070,578 2/1937 Bowman 55/223 APPARATUS 3,633,882 1/1972 Karakawa etal. 261/114 R John Dunn, Mountvale, NJ.

Peabody Engineering Corporation, New York, NY.

Filed: Apr. 28, 1972 Appl. No.: 248,426

Inventor:

Assignee:

US. Cl 55/223, 55/238, 55/228, 55/229, 55/242, 44/244, 261/79 A, 261/114R Int. Cl 801d 47/00 Field of Search 55/223, 228, 229, 237, 55/242, 238,244; 261/79 A, 114 R References Cited UNITED STATES PATENTS 7/1933Urquhart 261/114 R Primary ExaminerFrank W. Lutter AssistantExaminer-Steven H. Markowitz Attorney, Agent, or Firm-N. L. Leek; RobertH. Bachman ABSTRACT A bubble tray for gas washing apparatus adapted tocarry a blanket of wash liquid and having rows of holes through whichthe gases pass into the liquid. A curved deflector plate forming acircular channel is disposed over each row of holes with a longitudinalopening registering with the holes to receive the rising gases. Thegases enter the channel tangentially through a constricted passage tocause the liquid to rotate therein and to deposit the entrainedparticles centrifugally onto the circular walls of the plate.

13 Claims, 4 Drawing Figures BUBBLE TRAY FOR GAS WASHING APPARATUS Thisinvention relates to gas washing apparatus of the type having a bubbletray carrying a layer of wash liq uid through whichthe gases pass andwhich is adapted to entrap and remove suspended particulate material. Anobject is to provide apparatus of the above type having novel andimproved operating characteristics.

A feature of the invention is the provision of a deflector plate havinga curved portion forming an inverted substantially circular channelhaving a longitudinal opening which is disposed in alignment with theholes in the bubble tray. The gases pass into this channel substantiallytangentially through a constricted passage and cause the liquid in thechannel to rotate and to form a mixture of air and liquid from which theparticulate material is separated centrifugally. The gases and liquidpass longitudinally along the deflector and are discharged at theendsthereof or through various openings in the deflector wall. a

The nature of the invention will be better understood by referring tothe following description, taken in connection with the accompanyingdrawing in which a specific embodiment has been set forth for purposesof illustration.

In the drawing:

FIG. 1 is a vertical section through a gas washing apparatus embodyingthe present invention with parts in elevation; I

FIG. 2 is a section taken on the line 2-2 of FIG. 1

I showing the arrangement of the deflector plate;

FIG. 3 is a partial section taken on the line 3--3 of FIG. 1 showing theconstruction of the access pipe and valve; and

FIG. 4 is a partial section similar to FIG. 2 but on a larger scale toillustrate the details of the deflector plate and the constrictedpassage.

Referring to the drawing more in detail, the apparatus is shown asembodying a vessel having side walls 11, a coned top 12 and a conedbottom' 13. The bottom 13 is formed with an inlet port 14 surrounded bya flange 15 which rests upon the cover 16 of a receiver 17 having a portregistering with the inlet port 14.

The vessel 10 is shown as having twobubble trays 20 which are oppositelyinclined for the flow of liquid from one to the other. The trays may,however, be mounted horizontally if desired. Each tray 20 is providedwith a plurality of rows of holes 21 through which the gas passes andbubbles upwardly through a liquid layer 22 which is held on the tray bya weir 23 at the lower side of the tray. Liquid which flows over theweirs 23 passes to the tray below or through the bottom port 14 into thereceiver. The liquid is prevented from passing through the holes 21 bythe pressure of the upwardly flowing gases.

Disposed over the rows of holes 21 are a series of deflector plateshaving a lower substantially straight portion 31 which is supportedabove the surface of the bubble tray 20 by supporting feet 32. Extendingupwardly from the portion 31 is an arcuate portion 33 which may extendaround a substantially 345 arc to form a channel 35 of substantiallycircular section, leaving an opening 34 which is disposed directly overthe holes 21. The straight portion 31 is shown as slightly inclined andtangential to the arcuate portion 33. The trailing portion 38 of thearcuate wall 33 is inclined upwardly toward the passage34 to form withthe inclined wall 31 a converging venturi type passage 39 disposed abovethe holes 21 through which the gases and liquid enter the circularchannel 35. The gases and liquid are thus injected into the channel 35with an increased velocity due to the venturi action of the convergingpassage 39 and caused to rotate rapidly within the passage 35 so as toseparate centrifugally the particular material and liquid from thegases.

The stripped gases collect in the upper portion of the channel 35 andpass along the channel until they reach a vent opening 37. The gasesthen pass upwardly through the remaining portion of the liquid blanket22 carrying a part of the liquid in the form of a spray which impingeson the undersurface of the next bubble tray 20 or, in the case of theupper tray, they pass into the drying zone 40 which may contain dryingapparatus of any desired type for stripping the remaining liquid fromthe gases. The dried gases are then discharged from the top opening 41.Gas flow may be induced by a blower (not shown) in either the inlet orthe outlet duct. The wash liquid containing the entrained particulatematerial passes through the bottom opening 14 into the liquid in thereceiver 17 where the particulate material settles out as a sludge whichmay be removed by any suitable means through discharge pipe 45. Theliquid level is maintained in the receiver by a supply pipe 46.

The gases to be cleaned are fed into the vessel 10 through an inlet duct47 and the cleaned gases are removed through outlet duct 48.

The liquid from which the solids have been removed may be recycled bypassing through a filter, not shown, to a pump 50 from which they arefed by pipe 51 into the vessel 10 at a point above the topmost tray 20and through a pipe 52 extending below the lowermost tray and havingspray openings 53 adapted to discharge a spray 54 onto the underside ofthe lowermost tray for washing the same and also for prewashing thegases for removing the larger suspended particles.

The particulate material is removed from the wall 33 of the plate 30 byinserting a brush 55 through a pipe 56 which registers with the channel35 and extends through the wall 11 of the vessel 10. The inclination ofthe trays 20 and of the pipes 56 is such that the opening is above thelevel of the liquid on the trayso that no liquid escapes. A closurevalve 57 may be provided to seal the pipe 56 between cleaningoperations. In the event that the trays are positioned substantiallyhorizontally so that the opening would be below the liquid level asuitable air lock may be provided to prevent escape of liquid duringcleaning.

The weir 23 is of a height to maintain a depth of liquid sufiicient tosubmerge'the various deflector plates 30 and the channels 35 therein.

What is claimed is:

1. Gas washing apparatus comprising a housing arranged to yield upwardlyflowing gases containing particulate matter, a bubble tray arrangedacross the gas flow path having rows of holes through which the risinggases pass and said tray carrying a blanket of liquid,elongated-deflector plates mounted on said tray and curved to formsubstantially circular channels therewithin and having longitudinalopenings therein disposed above and arranged in direct fluid flowcommunication with the rows of holes in such a manner that gases fromsaid holes and liquid from said tray pass into said channels to form arotating gas-liquid mixture which deposits the entrained particulatematter centrifugally onto the walls of the plates and means forseparating the thus cleaned gas from the liquid. i

2. Apparatus as set forth in claim 1 in which said plates are submergedin said blanket.

3. Apparatus as set forth in claim 2 in which said plates have gasdischarge openings in their upper portion.

4. Apparatus as set forth in claim 1 in which said deflector plates areformed with an inclined substantially straight portion terminating in anarcuate portion having its trailing edge spaced from said first portionto form said openings in fluid flow communication with said rows ofholes. 1

5. Apparatus as set forthin claim 4 in which the trailing part of saidarcuate portion is inclined upwardly to form with said first mentionedinclined portion a converging passage through which the liquid and gasespass into said circular channel.

6. Apparatus as set forth in claim 5 in which the walls of said arcuateportion extend through substantially 345.

I 7. Apparatus as set forth in claim 1 including a plurality of saidtrays in which said trays are provided with weirs to maintainsaid'blanket of liquid thereon.

8. Apparatus as set forth in claim 7 in which said trays are inclinedfor the flow of liquid over said weirs onto the next succeeding traythrough downcomers.

9. Apparatus as set forth in claim I in which said trays are disposed ina vessel having side walls and openings are provided in said side wallsinregistration with the respective channels for the insertion of acleaning tool.

10. Apparatus as set forth in claim 9 in which said side wall openingsare disposed above the level of the liquid of said blanket.

. 11. Apparatus as set forth inclaim 1 including a stack of said traysand means disposed to wash the underside of ,the lowermost tray. 12.Apparatus as set forth in claim 1 in which a plurality of trays arestacked in said housing and including a. pump connected to recirculatewash liquid onto said trays for maintaining said blanket of liquidthereon.

13. Apparatus as set forth in claim 12 including a particulate mattersettling receiver disposed below said housingto receive wash liquid fromsaid trays andin which the separated particulate material settles out assludge, and means to recirculate the thus cleaned liquid from saidreceiver onto said trays for maintaining said blanket thereon.

1. Gas washing apparatus comprising a housing arranged to yield upwardlyflowing gases containing particulate matter, a bubble tray arrangedacross the gas flow path having rows of holes through which the risinggases pass and said tray carrying a blanket of liquid, elongateddeflector plates mounted on said tray and curved to form substantiallycircular channels therewithin and having longitudinal openings thereindisposed above and arranged in direct fluid flow communication with therows of holes in such a manner that gases from said holes and liquidfrom said tray pass into said channels to form a rotating gas-liquidmixture which deposits the entrained particulate matter centrifugallyonto the walls of the plates and means for separating the thuS cleanedgas from the liquid.
 2. Apparatus as set forth in claim 1 in which saidplates are submerged in said blanket.
 3. Apparatus as set forth in claim2 in which said plates have gas discharge openings in their upperportion.
 4. Apparatus as set forth in claim 1 in which said deflectorplates are formed with an inclined substantially straight portionterminating in an arcuate portion having its trailing edge spaced fromsaid first portion to form said openings in fluid flow communicationwith said rows of holes.
 5. Apparatus as set forth in claim 4 in whichthe trailing part of said arcuate portion is inclined upwardly to formwith said first mentioned inclined portion a converging passage throughwhich the liquid and gases pass into said circular channel.
 6. Apparatusas set forth in claim 5 in which the walls of said arcuate portionextend through substantially 345*.
 7. Apparatus as set forth in claim 1including a plurality of said trays in which said trays are providedwith weirs to maintain said blanket of liquid thereon.
 8. Apparatus asset forth in claim 7 in which said trays are inclined for the flow ofliquid over said weirs onto the next succeeding tray through downcomers.9. Apparatus as set forth in claim 1 in which said trays are disposed ina vessel having side walls and openings are provided in said side wallsin registration with the respective channels for the insertion of acleaning tool.
 10. Apparatus as set forth in claim 9 in which said sidewall openings are disposed above the level of the liquid of saidblanket.
 11. Apparatus as set forth in claim 1 including a stack of saidtrays and means disposed to wash the underside of the lowermost tray.12. Apparatus as set forth in claim 1 in which a plurality of trays arestacked in said housing and including a pump connected to recirculatewash liquid onto said trays for maintaining said blanket of liquidthereon.
 13. Apparatus as set forth in claim 12 including a particulatematter settling receiver disposed below said housing to receive washliquid from said trays and in which the separated particulate materialsettles out as sludge, and means to recirculate the thus cleaned liquidfrom said receiver onto said trays for maintaining said blanket thereon.